Starry sky

One of the Unit Telescopes (UT) of ESO's Very Large Telescope (VLT) swivels to fix its gaze on the target of its observations as the sky appears to turn overhead, due to Earth's rotation on its axis. The bright band of our own galaxy, the Milky Way, is visible in the star-filled sky. Each individual UT has a main mirror 8.2 metres in diameter, and can see objects four billion times fainter than what can be seen with the unaided eye. In the foreground is one of the VLT's four Auxiliary Telescopes, which feed data to the VLT Interferometer, enabling still higher-resolution images.